The present invention relates to hydroponic growing apparatus and more particularly to hydroponic growing apparatus wherein individual planting cups are utilized to substantially isolate the sterile support media from the direct flow of the nutrient enriched liquid.
In recent years, there has been a dramatic resurgence in the development and use of hydroponic growing systems (i.e., growing plants in water containing essential nutrients without dependence upon soil) in both commercial and residential applications. Such hydroponic systems have the advantages of controlled or regulated water and nutrient supply to the plants which has been found to substantially increase the growth rate and overall productivity of the plant.
Typically, prior art hydroponic systems have comprised plural open top flat bed containers which are nested one on top of the other in a vertical orientation. The upper container typically supports a sterile support media such as vermiculi, into which is inserted a plurality of individual plants, whereas the lower container typically forms a storage reservoir for the nutrient enriched solution. In operation, the nutrient solution is circulated from the lower to upper container by either (1) drip irrigation, where the prepared solution is dripped into the sterile media, (2) wick irrigation, wherein a wick transfers the solution from the lower to the upper container, or (3) flood irrigation, wherein the solution is pumped through the support media and allowed to drain out into the reservoir. Although all of these prior art hydroponic systems have proven useful in their limited application, there exists inherent deficiencies in their overall operation.
In particular, the prior art systems are highly susceptible to media contamination due to the direct exposure of the support media with the nutrient liquid flow. By dripping or flooding the support media directly with the nutrient solution, the media acts as a filter which after prolonged use, accumulates undissolved salts and other organic materials. Such filtration build-up increases the pH balance of the media and also adversely affects the sterility of the media often causing root and soil type diseases to propagate and damage the plants.
Additionally, with typical prior art hydroponic systems, there are no provisions for easy removal of individual plants from the apparatus. Each time a plant is desired to be removed from the apparatus, the plant must be pulled or dug out of the media usually resulting in a substantial portion of the root structure being broken off and left behind in the sterile media. After a short period of time, these broken roots begin to decompose causing contamination of the media which progressively alters the chemical makeup or quality of the nutrients available to the plant. In this same regard, the broken roots often pass into the reservoir lodging in restrictive areas of the flow conduits or entering into the internal components of the pumping unit thereby causing system blockage.
The open growing bed design of the prior art hydroponic apparatus is also extremely vulnerable to excessive evaporation of the nutrient solution as well as periodic flooding by rain. Excessive evaporation of the water from the nutrient solution yields an abundance of nutrient materials being provided to the plant, which, in most cases, effects plant growth. Alternatively, if the hydroponic apparatus is exposed to substantial rain, the growing bed and/or reservoir may become flooded thereby resulting in excessive moisture in the plant bed which causes root rot and dilution of the nutrient liquid in the reservoir. As such, the prior art hydroponic growing apparatus have typically been located in greenhouses wherein evaporation may be controlled and exposure to rain may be eliminated.
Further, due to the filtration of the media in the prior art and the failure to provide for easy plant removal, the prior art systems require frequent system clean-outs. These clean-outs necessitate that all of the plants growing in the bed be dug up and removed, the growing media be thoroughly rinsed or replaced, and the subsequent repositioning of the media and plants back into the growing bed. In addition to the substantial period of time to complete the clean-out procedure, it is often necessary to plant new plants in the bed since the more mature plants will be damaged and severely shocked when removed from the media.
In addition, the majority of prior art hydroponic growing apparatus have comprised relatively large and expensive systems being specifically adapted for commercial greenhouse applications. As such, there exists a need for an economical residential and/or commercial hydroponic growing apparatus which prevents contamination of the sterile media, provides for easy removal of individual plants from the apparatus and may be effectively utilized in outdoor applications without the need for a greenhouse environment.